There is a legacy of radioactive and chemically hazardous wastes at contaminated sites and facilities throughout the United States. Further, there is an initiative to establish and conduct an integrated program for the development, testing, evaluation and deployment of remediation technology to characterize, retrieve, treat, concentrate and dispose of radioactive waste stored in underground high-level waste tanks at these various contaminated sites and facilities. A large portion of the tank waste exists as a liquid solution (supernate) that contains soluble radionuclides, along with high concentrations of sodium and potassium salts. In general, the fission product radionuclides constitute less than 0.1% of the waste by mass and cesium is the primary source of radiation, especially highly penetrating gamma radiation. As a result, the majority of the liquid can be disposed of as low-level waste (LLW) at a much lower cost if the radioactivity can be reduced below the regulatory limits.
Thus, there is a need in the art to design and develop efficient and effective chemical processes and equipment for removing cesium and other radionuclides from bulk liquid LLW supernate, and concentrate it into a small high-level waste (HLW) fraction, to protect people and the environment from the hazards of the waste. More particularly, there is a desire to design and develop an ion-exchange column that includes integral shielding, cartridge configuration, inherent cooling and, the ability to be used and subsequently undergo interim safe storage in the absence of active safety systems.